Make your pendrive "virusproof"

Follow the steps below:

1st step:Format your pen drive as FAT32 (right click on your pen icon and click format).        If your pen has the format as NTFS option, click there and skip to step 3.

2nd step: Now we are going to convert the pen drive to NTFS, open cmd.exe and type "convert e: /fs:ntfs" (without quotes), where "e:" is the pen drive letter attributed by windows 

3rd step: Open mycomputer->Organize->folder and search options->View Tab and untick "use sharing wizard"

4th step: Make a new folder in your pen drive, and from now you will put your files in that folder

5th step: Now right click in your pendrive icon, click properties and go to the security tab

6th step: In permissions for all users only leave ticked the "read and execute", "list folder contents", and "read"

7th step: Repeat step 6 but instead of setting the security parameters to the pendrive do it only for the folder that you created inside it.(Now edit permissions again to all users but now give total control)

By doing this your flash drive will not allow to be written or executed at its root, where they host the malicious files on your pendrive, the folder that you created will have total control and without the existence of virus. Unless you put yourself there an infected file of course.